A case of spontaneous hemoperitoneum presenting as the initial manifestation of systemic lupus erythematosus.

Thrombocytopenia is included in the classification criteria for systemic lupus erythematosus (SLE). However, severe thrombocytopenia causing spontaneous bleeding is rare. Here, we describe a 22-year-old woman who presented with spontaneous hemoperitoneum as the first manifestation of SLE. Laboratory findings compatible with SLE included positive antinuclear antibody and a false-positive venereal disease research laboratory. Symptoms suggesting the disease were not prominent early after admission, but headache and seizures that developed on the 3rd day of admission led to the diagnosis of SLE. The brain magnetic resonance imaging and angiography findings were compatible with the neuropsychiatric manifestations of SLE. High-dose steroid and monthly intravenous cyclophosphamide pulse therapy were effective at improving the headache and seizure, as well as the hemoperitoneum.